Progesterone appears to be the best method of providing luteal phase support, with a relatively higher live birth rate than placebo, and a lower risk of ovarian hyperstimulation syndrome (OHSS) than hCG.
[1] The live birth rate is significantly higher with progesterone for luteal support in IVF cycles with or without intracytoplasmic sperm injection (ICSI).
[1] The main ones are: The time for beginning luteal support can be put in relation to various events: Luteal support given for a shorter duration than 7 weeks results in an increased risk of miscarriage in women with a dysfunctional corpus luteum (as can be diagnosed by blood tests for endogenous progesterone).
[12] In general, however, luteal support can safely be discontinued at the time of a positive pregnancy test (approximately 2 weeks after fertilization).
[1] In fact, luteal support with human chorionic gonadotropin (hCG) alone or as a supplement to progesterone has been associated with a higher risk of ovarian hyperstimulation syndrome (OHSS).